OLED, i.e. organic light emitting diode, also named “organic electroluminesence display (OELD)”, is a new generation of lighting display device, in which organic light materials is filled in a space between a transparent anode and a metal reflective cathode and a voltage can be applied to the organic light materials for lighting. Because OLED doesn't need a backlight device, so that it can be manufactured relatively thin. Compared to other type panel display devices, OLED consumes less electric power, OLED can work within a wider range of temperature, and the manufacturing cost thereof is relatively low. Therefore, its application gradually becomes wider. Furthermore, organic light emitting materials having various colors can carry out various colors in displaying. For example, referring to FIG. 1, FIG. 1 is a schematic view of pixel structures of OLED display device, wherein each of pixel units comprises sub-pixels R, G and B, and sub-pixels R, G and B are used to provide various visible lights, such as red light, green light and blue light.
Moreover, with the development of quartz glass, package techniques, electric vacuum industry and ultraviolet spectrum techniques, ultraviolet lighting are widely utilized day by day, wherein the ultraviolet light comprise mercury arc lamp, metal halide lamp, electodeless discharge lamp, xenon lamp, ultraviolet excimer lamp and ultraviolet (UV) emitting diode. Within ultraviolet lighting, as described above, the most used is gaseous ultraviolet lighting. However, the gaseous ultraviolet lighting have problems that main materials are high toxic, secondary pollution is potential existed and device is inconvenient to use and easy to be broken.
In contrast, an emerging ultraviolet-organic light emitting diode (UV-OLED) has advantages in environmental protection, low-cost, easy large-area production and easy integration to flexible substrate, so as to make up the shortage of the conventional ultraviolet lighting. However, if UV-OLED is separately produced, the usage is not widely enough, and its application is certainly limited.
It is therefore one of directions in OLED researching field to think how to combine OLED display with ultraviolet lighting to form a new OLED display device for carrying out colorful display and being used as an ultraviolet light source.